Neoden TM240A Pick and Place machine – first impressions

By Oleg Mazurov

TM240A building USB Host Shields

Some time ago I noticed that I’m spending more time building boards and less time developing and needed to increase my manufacturing capabilities. After thorough reading Dangerous Prototypes’ Chinese desktop pick and place machine forum thread I got in contact with a factory and bought TM240A – the big brother of TM220A. Earlier this week a DHL van carrying 70kg crate pulled in my driveway. After a day of hands-on learning I started building boards. This article was written after 2 days of using the machine and contains my first impressions as well as a couple of hints.

First, it is a real Chinese machine – well built, simple, and reasonably priced. At the same time, an owner must be prepared to fix mechanical issues and work around software bugs without relying on manufacturer’s support – the folks at Neoden are helpful but due to a time difference a reply to an e-mail would arrive the next day. Fortunately, the user base for these machines is expanding and the thread linked above as well as videos by Ian@DP and other people provide lots of useful info.

I was ready to face issues like air lines clogged by small pieces of styrofoam, non-functioning vacuum pumps and such; luckily, the only problem out-of-the box was racked gantry causing feeding fault. Thanks to this post in DP thread I was already aware about the symptoms as well as the fix – so I fixed it. While doing this I learned that to implement the fix no tools were necessary – a typical human finger jammed between the front support and the gantry works just as well as originally specified screwdriver.

I loaded some tapes and proceeded to stuffing boards. During test runs double sided removable scotch tape placed over the pads helped keeping parts in place. “Removable” type is preferable since it leaves no residue. Also, since the machine has no vision, accurate board registration is paramount. Here is how I do it.
The machine has a laser pointer shaped as crosshairs. With this shape it is easier to aim if a reference board feature AKA fiducial resembles a cross. When there is no fiducial, a reference point can be produced from existing land pattern, as follows.

A picture below shows the Eagle file for a panel of USB Host Minis. Each board contains MAX3421E chip packaged in TQFP-32.

A panel of USB Host Minis

Next picture shows closeup of MAX3421E land pattern on lower left board in the panel. I need coordinates of intersection of a grid lines passing through centers of pads 16 and 17. The coordinates can be derived from the library part (it is X of pad 17 and Y of pad 16 subtracted from the position of the center of the part itself) or simply read from the Eagle screen by placing a cursor on the intersection. This gives me one fiducial. Second one can be obtained from the MAX3421E land pattern on the upper right board in a similar manner.

Reference point

After that, both pairs of coordinates can be used to produce fiducial parts in a placement file ( see DP TM220A wiki for more information about file format). Here’s the fragment of mine:

When file is loaded in the machine the parts can be used to check/adjust board alignment. Next picture shows laser pointer showing position of Fiducial1. The difference between tinned pad and surrounding solder mask is clearly visible, especially when USB microscope (not shown) is used.

Board alignment

After one diagonal point is aligned the machine can be moved to the second one to check. The issue with registration on this machine is that one side of a board will always be parallel to the gantry. Some of my boards are cut at a slight angle due to the boardhouse being sloppy – for those I will need to fabricate a jig which would allow board rotation. This is going to be my next project. Stay tuned!

42 comments to Neoden TM240A Pick and Place machine – first impressions

What is the tqfp pitch the .5mm spacing I seen in the manual it could not do?
I also seen it could not do 100 pin tqfp .5mm…
So that is why I felt I should keep looking even thow I was probably equaly excited and wanted one of thowse machines.

Dear Oleg,
Have purchased TM240A and quite hapoy with it. I would like to use head 1 to «pick up» a point of (cold curing conductive) glue placed in stack 0. I imagined to plug one of the tips, so the vacuum would mention «all ok». Do you have any Idea how to use one head to dip into an adhesiv and to touch the board somewhere? Kind regards, Daniel

My fear would be, that the adhesive would be sucked into the system, cold cure inside, destroying the ability of the machine to process standard SMD elements. Would be a solution if there is a filter somewhere inhibiting this worst case. Custom nozzle would be less dangerous indeed. Any idea from whom?

Hi,
Just wanted to thank you (and Dangerous Prototypes) for objective and good info on the TM240A.
I got one in July, and it has already almost paid for itself. Using much less time on small series (up to some hundred PCBs) and the quality ‘bottleneck’ now is soldering; vapor phase DIY with cooling and vacuum would have been fine for Leadless paste.

You can’t. After picking from the first position the machine automatically steps 18.01 mm to the right for the next part in stack 0 until 10 steps are made. It then goes back to the first position and so on.

If you have several different parts to be placed from stack 0 you need to make a separate job file for each one of them except the first one (which can be placed in the same job as all the taped parts).

It probably will if you bend the fingers out a little. They can also be removed quite easily; I have a board with parts so close to the edge that they are interfering with the fingers. I populate this board with fingers removed, the spring action of movable clamp jaw is enough to keep it in place.

Rcvd my TM240a this week.
Was surprized how well it was packed.
After a few days of playing ( as time permitted ), the unit is fully functional and seems to be pretty accurate.
Loading the reels is a bit o a pain, as I suspect is the norm with any PnP machine. I did have one reel of 33u tant caps that would not feed, tried a different stack position and same results, so I concluded it was the reel.
The touch screen is kinda nice when you get used to it, you can change the chinese headers in the config files to english to better read the screens. Do this on your PC as you config the PnP file.
The unit will not allow you to actively set the origin of the board, it is set and try method, why they did this makes no sense. It should be similiar to the manual feature when placing a component, you can use the buttons to move the laser int position.
Alas, its a nice machine, and tomorrow I will populate 5 boards and hope for the best.

Just to clarify:
You CAN set the Origin location to any point on your board, but not actively, that is, move the head and watch the laser move step by step. You have to enter X/Y then move the head to the new position, would have been nice to move it actively with the coordinate (up/down/left/right) buttons on the fly.

It is in the manual. You should have received a tool for it, a 2mm hex wrench. The tension adjusting screw is on the side of the spool I believe there is a picture in the manual showing how to do this.

Another comment:
The front tray (Stack 0 ) is handy but the draw back with this front tray is it is treated as a typical (reel).
I’ll explain….
You place your component in the first (left) tray and set up the center position of the component for pickup. This works great. Just keep in mind that this is STACK 0.
You can only use the ‘same’ type component in the following trays, so this is typical of a reel of components.

My take on this is it would be nice to be able to mix and match components in these trays for the one of a kind placement of parts on your boards.
But once you set the pick up position for the first part (tray 1) it is the same for each tray after that and will not pick up a larger or smaller component in the center as needed if they are different footprints.

So keep in mind that the front trays (STACK 0) must be the same style component. ie. all 1210, ssop-16, so-8 etc.

Note: if you have 4 different type chips, say MAX32xx, MAX 541, etc….and they are all the same footprint, ie. SO-8 parts, this works great just plan your PnP file accordingly for picking of these parts. So there is some flexibility, but you will need to evaluate this against just hand placing them.

I make several separate jobs for tray 0. Most typical case is the reel of 5032 crystals – the machine decides to reject some of them or having issues picking and I end up with a pile of loose parts. Instead of placing them manually I set “skip” for this part in the main job and then run another job consisting of picking it from tray 0. You can even have both lines in the same job, skipping one or another. This doesn’t work with small parts though – MS-8 package is marginal and anything smaller is impossible.

Ran the five boards and they went well.
I only ran at 50% speed to watch the process but it seemed to place pretty accurate.
There were a few components that were skewed but i left them that way and put into reflow oven to see if they would be pulled straight and they were!

All in all I think the unit is a good solution for small shop use, not sure its worth it for one off type boards as hand place will be faster than setting up the machine.
But we do large runs of one particular board and this will be a time saver on the run of 500+ boards.

Lastly we talked about the front tray, well I am going to have a custom front tray built, probably from G10 FR4 , to allow me to place the more lower profile compoments like 2512 resistors etc.

I did get the password from the vendor to allow setting change, but would recommend anyone attempting this be sure to write down the original values and store them to allow you to return the machine to the factory settings. Best yet just leave them alone. But for the price I wanted to have this access even if I did not plan to use it.

The TM240 machine is the better size with more reels, consider carefully your need if you are thinking about the smaller TM220A unit as the smaller number of reel placement can be a hassle if you have to change them out alot.

Earlier I mentioned I had a reel of 33u SMD caps that would not feed.
I founf the part wa too wide for the feed through. ( the guide that the reel is pulled through )
I took the two guide screws off the guide plate, and noticed that the part would skew to one side as I pulled the tape through.
So I modified the U shape guide by opening it up on the side closest to the front.
Imused s standard dremel grinder tip with a flat tips and opened the width of the U channel to allow the part to properly feed.
It now feeds very nicely and with no binding.

As I can read somewhere you have 2 control boards for this machine ?
Many people are asking what kind of processor they are using, could you please let us know ?
Is it possible to order from Neoden any spare parts ?
What is hard to understand for me is that the pasword is not provided on purchase.
I will receive my machine within 3/4 days, it is now in Germany … not far from my place in France … after this weekend, I’m so excited.
Serge.